In seeking to vary the surface on which our gardening is to be done, our attention falls first upon the three simplest forms of ground: the plane, the concave, and the convex surfaces. And we note also that the concave and convex surfaces give in themselves a much greater variety of view than is afforded by a plane.

This is so potent a principle that, in making up the surface of the grounds for park or residence purposes, great care is usually taken to avoid a perfect plane, and still to give a uniform swell or depression. Breaking the plane with a succession of little hillocks would be fatal indeed. Of these three classes of surface the concave is usually to be preferred for small areas, for it gives much the best effect of extent. From any point within a concavity the whole surface is visible. This is not true of a convexity; and a perfectly flat surface will seem rather bland, unless given some bold and striking treatment.

Caution needs to be taken to secure the best use of these several varieties of surface. As long ago as 1770 Thomas Wheatley said:

"In made ground the connection is, perhaps, the principal consideration. A swell which wants it is but a heap; a hollow but a hole; and both appear artificial. Such shapes should be contiguous as most readily unite; and the actual division between them should be anxiously concealed. If a swell descends upon a level; if a hollow sinks from it, the level is an abrupt termination, and a little rim marks it distinctly. To cover that rim a short sweep at the foot of the swell, a small rotundity at the entrance of the hollow, must be interposed."

All these cautions are fully worth attention, for the slightest differences in the surface of the ground are obvious and important to the sensitive beholder. Broken ground offers an evident and spicy variety. The value of broken ground for developments of the picturesque is to be especially considered.

Sloping grounds have a value all their own, and for their most effective utilization, require a special treatment. For the present we will content ourselves by saying that two opportunities are afforded the gardener by sloping grounds which are elsewhere unusual.

The first is in the diversity of surface presented. The second is in the advantageous situation for the display of many plants in planters which, in any other position, would not appear to advantage. With respect to the first, it should be explained that even comparatively gentle slopes may be emphasized by proper treatment until they appear to be steep declivities.

The first expedient to this end lies in the treatment of the ground itself. Simply contrive small irregularities of the surface by placing here and there a little swell which rises abruptly and then falls away gradually down the hill. This part of the declivity will be steeper than the general slope, and a few of these contrasts will give the appearance desired.

Such variety is often to be sought on a flat and featureless place. A slope also furnishes a suitable location for the disposition of rocks, both because they are needed to hold the hillside against washing by rains, and because they appear at a much better advantage than on level ground.

If the rocks used on a hillside are obviously misplaced, they should always be disguised, or hidden with grass and shrubs and trailing vines. These give great satisfaction if allowed to run at liberty down the side of a bank.

Water in any form furnishes an ever pleasing addition to a garden, whether as a bubbling fountain, a sparkling brook, or a cool and quiet expanse of mirror-like surface. In brooks and ponds it furnishes one of the most delightful resources of the landscape gardener.

Besides the wonderful variety of pleasing effects of which it is in itself capable, it provides the only opportunity for growing many species and varieties of our most beautiful plants.

There are many simple things you can add to a garden to make it fit with the ground you have been given.